(a) Technical Field
A block copolymer and a method of forming patterns by using the same.
(b) Description of the Related Art
A method of forming patterns using a block copolymer has been researched since this method enables patterns having a line width of about 50 nm or less to be formed, and this method is also relatively simple and inexpensive. In addition, with the method of forming patterns using the block copolymer, various sizes of patterns may be formed by controlling the molecular weight of the block copolymer, and various types of patterns may be formed by controlling the molecular weight ratio of the block copolymer.
A morphological direction of the surface of a target object such as, for example, a substrate and the like may be controlled by a neutral surface treatment. For example, a hydroxy terminated random copolymer, a benzocyclobutene (BCB) based cross-linkable random copolymer, an azide based cross-linkable random copolymer, and the like may be used in the neutral surface treatment.
However, in the hydroxy terminated random copolymer, the processing time for forming the patterns may be long because a heat treatment time may take about 3 days. In the BCB based cross-linkable random copolymer, synthesis of BCB may be complicated and the processing cost may be expensive. In the azide based cross-linkable random copolymer, reaction efficiency of azide may be low. In addition, since the BCB based cross-linkable random copolymer and the azide based cross-linkable random copolymer do not form a covalent-bond with a substrate and use only crosslinks between polymer layers, adherence between the substrate and the polymer layer may not be strong.